第一部分：语法知识（20题，每题1分，共20分）
1. If a computer crashes, you will lose the file you _________unless you save it regularly.
A. are working B. work C. will work D. worked
2. The building burnt down in a big fire. ________was the base on which it stood.
A. What remained B. All remained
C. What was remained D. All what remained
